node_device: Expose link state & speed

While exposing the info under <interface/> in previous patch works, it
may work only in cases where interface is configured on the host.
However, orchestrating application may want to know the link state and
speed even in that case. That's why we ought to expose this in nodedev
XML too:

virsh # nodedev-dumpxml net_eth0_f0_de_f1_2b_1b_f3
<device>
  <name>net_eth0_f0_de_f1_2b_1b_f3</name>
  <path>/sys/devices/pci0000:00/0000:00:19.0/net/eth0</path>
  <parent>pci_0000_00_19_0</parent>
  <capability type='net'>
    <interface>eth0</interface>
    <address>f0🇩🇪f1:2b:1b:f3</address>
    <link speed='1000' state='up'/>
    <capability type='80203'/>
  </capability>
</device>

Signed-off-by: Michal Privoznik <mprivozn@redhat.com>

docs/formatnode.html.in

@@ -161,6 +161,13 @@
               <dd>The interface name tied to this device.</dd>
               <dt><code>address</code></dt>
               <dd>If present, the MAC address of the device.</dd>
+              <dt><code>link</code></dt>
+              <dd>Optional to reflect the status of the link. It has
+                two optional attributes: <code>speed</code> in Mbits per
+                second and <code>state</code> to tell the state of the
+                link. So far, the whole element is just for output,
+                not setting.
+              </dd>
               <dt><code>capability</code></dt>
               <dd>A network protocol exposed by the device, where the
                 attribute <code>type</code> can be "80203" for IEEE

docs/schemas/nodedev.rng

@@ -243,6 +243,7 @@
         <ref name='mac'/>
       </element>
     </optional>
+    <ref name="link-speed-state"/>
 
     <zeroOrMore>
       <ref name='subcapnet'/>

src/Makefile.am

@@ -1519,7 +1519,7 @@ libvirt_driver_nodedev_la_SOURCES = $(NODE_DEVICE_DRIVER_SOURCES)
 libvirt_driver_nodedev_la_CFLAGS = \
 		-I$(top_srcdir)/src/access \
 		-I$(top_srcdir)/src/conf \
-		$(AM_CFLAGS)
+		$(AM_CFLAGS) $(LIBNL_CFLAGS)
 libvirt_driver_nodedev_la_LDFLAGS = $(AM_LDFLAGS)
 libvirt_driver_nodedev_la_LIBADD =
 

src/conf/node_device_conf.c

@@ -389,6 +389,7 @@ char *virNodeDeviceDefFormat(const virNodeDeviceDef *def)
             if (data->net.address)
                 virBufferEscapeString(&buf, "<address>%s</address>\n",
                                   data->net.address);
+            virInterfaceLinkFormat(&buf, &data->net.lnk);
             if (data->net.subtype != VIR_NODE_DEV_CAP_NET_LAST) {
                 const char *subtyp =
                     virNodeDevNetCapTypeToString(data->net.subtype);
@@ -875,7 +876,7 @@ virNodeDevCapNetParseXML(xmlXPathContextPtr ctxt,
                          xmlNodePtr node,
                          union _virNodeDevCapData *data)
 {
-    xmlNodePtr orignode;
+    xmlNodePtr orignode, lnk;
     int ret = -1;
     char *tmp;
 
@@ -907,6 +908,10 @@ virNodeDevCapNetParseXML(xmlXPathContextPtr ctxt,
         data->net.subtype = val;
     }
 
+    lnk = virXPathNode("./link", ctxt);
+    if (lnk && virInterfaceLinkParseXML(lnk, &data->net.lnk) < 0)
+        goto out;
+
     ret = 0;
  out:
     ctxt->node = orignode;

src/conf/node_device_conf.h

@@ -29,6 +29,7 @@
 # include "virutil.h"
 # include "virthread.h"
 # include "virpci.h"
+# include "device_conf.h"
 
 # include <libxml/tree.h>
 
@@ -136,6 +137,7 @@ struct _virNodeDevCapsDef {
             char *address;
             unsigned int address_len;
             char *ifname;
+            virInterfaceLink lnk;
             virNodeDevNetCapType subtype;  /* LAST -> no subtype */
         } net;
         struct {

src/node_device/node_device_driver.c

@@ -39,6 +39,7 @@
 #include "node_device_driver.h"
 #include "virutil.h"
 #include "viraccessapicheck.h"
+#include "virnetdev.h"
 
 #define VIR_FROM_THIS VIR_FROM_NODEDEV
 
@@ -47,10 +48,13 @@ static int update_caps(virNodeDeviceObjPtr dev)
     virNodeDevCapsDefPtr cap = dev->def->caps;
 
     while (cap) {
-        /* The only caps that currently need updating are FC related. */
         if (cap->type == VIR_NODE_DEV_CAP_SCSI_HOST) {
             detect_scsi_host_caps(&dev->def->caps->data);
         }
+        if (cap->type == VIR_NODE_DEV_CAP_NET &&
+            virNetDevGetLinkInfo(cap->data.net.ifname, &cap->data.net.lnk) < 0)
+            return -1;
+
         cap = cap->next;
     }
 
@@ -315,7 +319,8 @@ nodeDeviceGetXMLDesc(virNodeDevicePtr dev,
         goto cleanup;
 
     update_driver_name(obj);
-    update_caps(obj);
+    if (update_caps(obj) < 0)
+        goto cleanup;
 
     ret = virNodeDeviceDefFormat(obj->def);
 

src/node_device/node_device_udev.c

@@ -40,6 +40,7 @@
 #include "virfile.h"
 #include "virpci.h"
 #include "virstring.h"
+#include "virnetdev.h"
 
 #define VIR_FROM_THIS VIR_FROM_NODEDEV
 
@@ -679,6 +680,9 @@ static int udevProcessNetworkInterface(struct udev_device *device,
         goto out;
     }
 
+    if (virNetDevGetLinkInfo(data->net.ifname, &data->net.lnk) < 0)
+        goto out;
+
     ret = 0;
 
  out: